Wednesday, November 27, 2013

A recent member of the Portland Transportation Twitterati queried about what the agency's best bike project was in 2013. It made me think about what accomplishments we have made with Traffic Signals in the past year (specifically related to bicycle traffic).

Implemented a new bike signal at SW 5th & Jackson associated with Portland to Milwaukie Light Rail construction. That project has taken up a lot of our staff time.

Implemented Bicycle/Bus Signal at 5th & Broadway

Edited Bicycle Signals language for the consideration of the Federal Highway Administration's inclusion in the next edition of the MUTCD.

Supported roadway reorganizations with technical analysis for PBOT projects on NE Glisan and SE Division to support improved safety (bicycle lanes were added on SE Division)

This sort of reflection is helpful, it's time to set some goals for 2014. I should go through this process for every mode.

There's a lot of work that happens that is just day to day making traffic signals better for people on bicycles. Today, I fielded a complaint that I have visited before on my bicycle, but figured that not many people use that street, so it wasn't worth fixing if I was the only one using the street via bicycle. Well, the customer is always right and in this case, there is a really minor change that can be made to make the signal "accessible" for someone on a bicycle (the signal head wasn't visible from someone in the bicycle lane AND there wasn't detection in the bicycle lane).

Thursday, October 10, 2013

This beacon was installed to help people on the I-205 cross SE Division Street. The original design was recently enhanced to provide an additional push button on the "right hand side" of the street. The added pole to the intersection and resulting costs were something that could be debated as whether it was necessary, but the additional pole eliminates the need for people to cross the oncoming multimodal traffic. The added pole frames the crossing and for an oncoming bicycle eliminates the need to cross to reach the push button on the left hand side of the "street".

It's not a major issue, but it is somethign that has come up on several occasions. As we have been building infrastructure that is designed for more than just for people walking, these sorts of design details seem worth sharing, so cycling is more intuitive and that users expect a push button or a signal indication on the right hand side of the street.

Sunday, September 29, 2013

Nearly every traffic engineer that has a shred of experience with research knows about Webster and the concept of an "optimal" cycle length at signalized intersections. The research completed by Webster is almost 50 years old yet the traffic signal timing tools that we use continue to use these days are based on these traditional methods. As I am reviewing the 2nd Edition of the Signal Timing Manual as the Chair of the National Cooperative Highway Research Program (NCHRP) project, I was very pleased to see this thoughtful text by the authors (lead by colleagues at Kittelson & Associates, Inc.)

critical intersection methods use Webster’s model to determine optimal cycle length, which has a de facto outcome focused on vehicle flow, not specifically considering the needs of other users, such as pedestrians, bicycles, and transit.

Bicycle traffic in downtown Portland (after a bridge lift)

There has been some work by my colleagues at the Texas Transportation Institute focused on the newer versions of the Highway Capacity Manual that focus on updating the 50 year old research and while that's good, the point of this post is to focus on the importance of policy. Policies should be carefully consulted in a cycle length selection process. The Signal Timing Manual, First Edition, highlights that in Chapter 2. Originally, that Chapter was met with some dismissive comments from the Panel of experts reviewing it. One professional cited too much use of the term "priority" meaning they didn't want transit to get special treatment.

A community with a emphasis on multimodal transportation should select cycle lengths that respond to the needs specific to the intersection. Lower cycle lengths are better for multimodal transportation in general. Lower cycle lengths are also best with shorter block lengths because of the potential for longer periods of red to stack traffic up between signals. Downtown Portland has both the policy and the aforementioned physical attributes (I originally wrote constraint but corrected myself because many consider this an asset) , that necessitate a very short range of cycle lengths: 48- (midday), 56- (a.m. peak), or 60-seconds (p.m. peak). These short cycle lengths provide quick changes for pedestrians.

Pedestrians in a downtown environment benefit from short cycle lengths In Portland, there's progression for pedestrians too, but that's another post.

and limited progression for buses that stop every two, three, or four blocks.

The progression speeds that follow from the short cycle length are slow to promote a safe environment for people on bicycles to take the lane and feel comfortable doing so.

Monday, September 23, 2013

I described my day job as traffic signals engineer and my volunteer night position as flyer producer for worthy causes like #walknbike day October 9th! Get excited and join me in getting the kids in the neighborhood to school in a multimodal fashion. I don't make flyers very often, but it was fun to think about how to share a message about something that used to be a very normal thing to do, but now has to be something that we take a day to make a big deal about and distinguish as a particular day that we walk & bike.

At the traffic signal immediately adjacent to our hotel, I sat and watched traffic for several hours marvelling at the range of vehicles, the behavior of travellers, and the integration of modes. My observations left me a little uncomfortable because pedestrians were often forced to yield to vehicles that were asserting their "right" to move in front of a legal movement.
The range of age of people at the intersection was also interesting, some of the people at the intersection that were the slowest seemed the most comfortable making movements that would make a traffic engineer like me cringe.

These photos are enjoyable because they represent just a few of the cargo bikes mixing with buses, heavy trucks, and passenger cars in the intersection.

Tuesday, September 17, 2013

I did not make up the acronym, I have to attribute that to my colleague, but here's a post on a new warning device in downtown Portland.

This "Bus Only Activated Transit Sign" (BATS) was activated by the City in cooperation with TriMet at their request. The intent of the sign is to warn pedestrians traveling in the east-west direction on Burnside of a bus approaching from the left turn (westbound direction). The warning sign is a caution indication designed to support the pedestrian indication as this is an area where TriMet has complained of a considerable amount of people walking in front of their left turning bus when they have a Don't WALK indication. Part of the "problem" in downtown is that there it is mostly just two phase intersections, so a left turn crossing maneuver is a bit of an anomaly. in most intersections, there isn't the expectation that this left turn conflict will be experienced and this one is particularly intermittent since it is a bus only movement and it only is active if a bus is present.

I have been invited to share some perspective on traffic signal operations for the Street Design Guide.

TRB 2014 Workshop on NACTO Urban Street
Design Guide

Sunday,
January 12, 2014

9:00am –
12:00pm

Hilton
Hotel

Summary

NACTO’s
Urban Street Design Guide charts the principles and practices of the nation’s
foremost engineers, planners, and designers working in cities today. A
blueprint for the 21st century street, the guide offers an inside perspective
into how cities can transform their streets to confront the demands and
challenges of the near future. From public plazas to BRT to stormwater
management, the guide provides an in-depth overview of how to design livable,
multimodal, and resilient city streets.

Topics:

9:00-9:20 Introduction
andOverview of Urban Street Design
Guide

Speaker: David
Vega-Barachowitz, NACTO

[David will add something re. his presentation]

9:20-10:00 Complete
Streets Across Different Street Types

Mike Flynn, NYCDOT

In an urban context, street design must meet the needs
of people walking, driving, cycling, and taking transit - all in a constrained
space. Mike Flynn will draw on NYCDOT’s experience in designing complete
streets for different sizes and contexts.

10:00-10:10 Break

10:15-10:35 Intersection
Design Principles

Michael King,
Nelson/Nygaard

As focal points of activity for pedestrians, drivers,
and cyclists, intersections are a critical part of the city streetscape and
transportation network. Good intersection design maximizes visibility and
creates a safe and intuitive space for people driving, walking and cycling,
promoting economic growth and active street life.

The use of interim materials gives cities greater
flexibility when making changes to the streetscape by enabling projects to be
implemented in the short term, allowing the community to weigh in on the
space’s effectiveness before creating the permanent condition. Examples
of interim materials use are plazas and parklets, pedestrianizing a corridor,
or redesigning complex intersections.

10:55-11:05 Break

11:10-11:30 Signalization
Strategies:

Peter Koonce,
Portland

The allocation of time by
traffic signals is as important as the allocation of space in governing how
streets operate. Signal timing tools such as Leading Pedestrian Intervals and
Split-Phasing can help ensure safe environments that support walking,
bicycling, public transportation, and economic vitality.

Thursday, August 29, 2013

The signage in China uses some unique elements that in the U.S. are a bit uncommon. The lane signage shows the separation of bikes and vehicle lanes (represented by the fence) with a solid line on the sign. The bike sign on the over head mast arm is supported by the post mounted sign which is at the fence. This particular street was a frontage road adjacent to the freeway in Beijing. The signal heads are over to the right which is not compliant with the MUTCD and I would be curious whether there is any significance to the location of the post mounted bicycle signal head and the two that are on the arm other than the need to provide some redundancy in case one of the red indications is out.

A few other observations is that there does not seem to be confusion between the bicycle signal display and the vehicular signal heads, as is sometimes described in the U.S. that could be that they used to have more bicycle traffic then they appear to have today, so most people are aware of what the bicycle indication is in reference to the other movements at the intersection.

I came across these Flying Piegons and thought of the old saying a "Piegons in every home" that seems like an antiquated concept in today's China. Yesterday's Piegons has been replaced with Buicks and Chinese model cars that are being produced at a record pace.

Wednesday, August 21, 2013

There is some debate over the benefits of Adaptive Control on the ITE listserv, here's my response:
Adaptive control is something that I thought was an effective strategy for dealing with changing traffic conditions. As a practitioner that has experience with the SCATS system, completed evaluation for the (now defunct?) OPAC initiative, and read the evaluations of the ACS Lite implementations completed by contractors (Sabra Wang) for the FHWA, it seems that they have their place, but the costs of the software and the modified detection are a lot for an agency to bear. There is also the cost of learning the software and having the maintenance and engineering staff know how to operate two different systems. As an agency with 1,080 signals, the City of Portland has 13 that are adaptive. The additional benefit of the 1%, that the City spent a significant amount of money to "improve" may have been better spent selectively throughout the system on technology that would have put information in the hands of the engineers that operate the remaining 99% of the signals. One could argue, (I could make this argument myself), that the limitation of resources across the board should not be the key limiting factor that we use in the cases, and there are communities like Bellevue, WA and Oakland County, MI (among others) that have installed enough of an adaptive system that their costs per intersection have come down significantly. My point is this, if an agency has a critical mass of intersections to apply an adaptive system than the engineers and maintenance staff have the ability to learn the system well enough to be effective in its operation. I will still contend there is a lot of functionality in our existing systems that we aren't using and effective gap setting, improved measurement of performance, and recognition and response of problems would serve us well. Here are my takeaways, I am curious if folks agree.

There are several situations where it is worth considering:
1. Surrounding event centers where the traffic ingress/egress are so variable that there isn't a great way to handle this (Portland uses some responsive control that works reasonably well at the NBA arena in Portland).
2. Applied where there is a significant number of intersections where the focus of several staff will handle the challenge of learning the new system.
3. If an agency is looking to mitigate congestion (as oppose to widening an existing street), adaptive control would likely increase capacity by being responsive to traffic increases in the shoulders of the peak by raising the cycle length earlier than a time of day plan. This is my opinion, studying these effects has not been done carefully (the Portland system included).

Significant limitations of the systems that need to be considered:
1. Limited ability to prioritize transit within the systems. The first answer from our vendor related to transit priority in the adaptive system was non-responsive.
2. Oversaturated operations. Does the system work better when traffic is queued up between intersections? Have you engineered the adaptive system to recognize when congestion occurs?

Monday, August 19, 2013

I was expecting to see good cycling
infrastructure while visiting China. I'd read a few stories highlighting how the status of the bicycle has fallen quite a bit in the past years and how cycling is not considered as a sport. Clearly, there is considerable status in having a car much as it is in the U.S. and on warm summer days in Hong Kong, I understand the usefulness of air conditioning. This post hopes to share the good and bad of Hong Kong cycling infrastructure.

One of the observed problems (which I will cover in more details later) is behavior of cyclists, but that's party a response to the lack of comfort they feel while using the facilities. It is partly due to conflicts from the other users of the streets, but also from the infrastructure provided. I liked the succinct comment I found with a quick search at http://www.whatsonningbo.com/health47.html: "44 percent of people in Beijing use their cars to travel distances of less than 5 kilometres. Most of these journeys could be made on a bicycle. So creating an environment to enable this social change is vital.Duan Liren, a traffic consultant for Beijing municipal government, says first and foremost Chinese road users need to understand the concept of Right of Way on bicycle. "If a thief steals 100 yuan, you know it's illegal. Actually this is as wrong as a vehicle driving in a bicycle lane."

2-way Cycletracks were provided on many of the streets we were on.At intersections, they use bollards to slow traffic to insure yielding.

As much as right of way and behavior is important, quality infrastructure is critical for people that want to use the facilities that are built. This post is a summary of some cycletrack elements we saw in the Northwest Territory of Hong Kong. In general, the City seems heavily influenced by British traffic (driving) standards and much like I have seen in London, most of the cycling infrastructure was not present on many of the
major streets. London is making major strides to change that by committing to a new plan just this past March. It's not just London that is making bold steps, but cities like New York City among others in the U.S., yet similarly there there are occasional challenges to this new infrastructure.

A weekend mountain biker weaves through the cars that are parked near the bollards.

Bollards at the intersections made it impossible to cycle side by sidewith another person continuously.

During our tour from a local we got to see some of the urban infrastructure. The visit and cycling tour in the NW Territory was a
good opportunity to experience the infrastructure from a local's
perspective.
The tour guide gave us a troup of the area nearby his home and then out into the “Wetlands, New Towns & Heritage Trails”.

The bollards took varioius form. In order to keep cars out of the facility, signs were placedat numerous locations even at some locations is might have been unnecessary.

A private driveway introduced a curve which made this intersection difficult to traverse, especially for a younger rider that may not be as confident on their bike.

As a part of the CICTP conference, we were afforded an opportunity
to visit the Shenzhen Multimodal Traffic Management Center. The TMC
was in what looked like a bus garage, but it looked like all of the
employees drove to work.
The operations of a City of 15 Million requires a large TV screen
to make sure you are getting the management activities right. Kidding
aside, it was an impressive set of screens across the room and must
have been 20 feet high.

GPS data from buses looks like L.A. DOT's system

The TMC gets information from many
sources. The sources include security cameras, traffic survelliance,
GPS transponders from taxis and buses (picture to the left), freeway speed (picture above) and flow
detectors, and freight data from the ports and the ships in the
harbor (picture below).

The TMC was impressive as most of them are, we wouldn't tour them if they were not going to have something to look at. One piece of feedback is that I wonder if the point of the TMC is for actual operations or more symbolic. It did seem like they had a good number of people working on code for their public information applications, they have one called "Traffic In Hand" that is available and it includes data and info on all modes including some of their bicycle shops that are available.

Freight shipping is tracked at the TMC

The TMC also provides a dispatch
function for pictures that are sent in by the public whth requests to
fix things (sort of like the Portland ap - PDX Reporter) which is nice for citizens to be able to help the City do its job even though there are times when the system is used incorrectly.

Video feeds from a wide variety of transit hubs.

They get a lot of
survelliance video from the airports, train stations, etc (4059). All
of the screens are linked to the workstations. We saw a lot of video cameras throughout the City while we were there and it wasn't clear whether they all come back to the TMC. If they are like the Portland version, there are different departments that have their own systems and they are not totally integrated, but that could be a thing of the past with shared communication systems and technology advances.

The most interesting application was that they have all of the
taxis connected with either a 2.5 or 3G cellular connection, so at
any point they can pull up where a taxi is and what the most recent
fares of the car have been. The polling rate was definitely sub minute level, so that they have a pretty good sense of travel times where the taxis are similar to the NYC Midtown in Motion project.

Taxi Automatic Vehicle Location system for fare checking providesinformation on what the last fares were for each driver in the system.

The Traffic In Hand ap also includes information about parking
lots, bus stops, and other
transit information including information on escalators in the
stations .